16S rRNA Gene and Metagenomic Analysis Revealed an Association Between Cecal Microbiota and Pork Umami

Umami is a key determinant of pork flavor, but the association between the intestinal microbial community and umami differences remains unclear. Here, we used the taste-sensing electronic tongue system to divide the Duroc × Landrace × Yorkshire pigs into high, medium and low groups. We combined 16S rRNA gene and shotgun metagenomic sequencing to study the differences in the microbial community composition and functional genes. The results showed that the microorganisms in the cecum of different groups had a similar core microbial community. The Shannon diversity analysis showed that there were no significant differences among the different groups. The Bray–Curtis distance indicated that there were differences in the bacterial communities between the high umami group and the other two groups. The LEfSe analysis and Spearman correlation analysis revealed that the uncultured species CAG-632 sp900539185 maintained a high abundance in the high umami group and was significantly correlated with umami. Metagenomic functional analysis revealed distinct functional signatures among umami groups, with enrichment of genes related to carbohydrate transport and metabolism, butanoate and other short-chain fatty acid pathways, nitrogen utilisation, cell-surface structures, adhesion and RNA metabolism in high umami groups. These research findings indicate that the differences in the delicious flavor of pork are more likely to be associated with specific microbial species and the functional characteristics of the cecal microbial community, rather than the overall situation of the entire microbial community.